#include<iostream>
#define PI 3.14
using namespace std;
class Circle
{
	double radius;
public:
	double get_r(double r)
	{
		radius = r;
		return 0;
	}
	double get_c()
	{
		return 2 * PI * radius;
	}
	double get_s()
	{
		return PI * radius * radius;
	}
};
class Bay :Circle
{

};
int main()
{
	Circle A, B;
	A.get_r(10);
	Bay gg;
	
	
	cout << A.get_c() << endl;
	cout << A.get_s() << endl;
	return 0;
}